Siphon-spillway.



Y H0 LLWAY.

TION FILED FEB.3,1913.

APPL

Patented Jan. 13,*1914.

3 SHEETS-SHEET 2.

v Fay 5 wI'rNEssEs':

9J F'zf 7 l INVENTORS M011/- AT1-Y.

Patented Jan- 15111914 a sm'zmsfgvg-a.

IN VEN TORS A 'TTY imi Qn, MQ on SIPHON SPILLWAY.

APPLIUATIQR FILED FEB. 3, 1913.

W. R. DAVIS d; G. E.- STICKNEY.

WITNESSES:

MJ, MQ #Y 2 it appertains to make and use the same, reference being had to the accompanying drawings, and to letters-or figures'ot reterence UNITED STATES PATENT orrrcnff wrLrnAM RUSSELL DAVIS AND GEORGEF. 'sTiCKNESn or LBA'NYy-Nnw YoRK'.

sIPHoNv-srILLwAYL- ISpecification of Letters Patent. y i Pafnted-Jn. 13, 1914.'

Application tiled Feblruary 3, 1913. Serial No. 745,7-82.

T0 all whom it may concern -Be it known that we, VILLIAM RUssnLL DAvis and GEORGE F. STICKNEY, citizens ot the United States, residing at Albany, in the county, ofAlbany and State of New York, have invented certain 'new' and useful Improvements in SiphonSpillways; 'and We do .declare .the following to ybe a full, clear, and" exactdescriptionot the invention, such as Will enable others skilled in the art to which marked thereon, which form a' 'partlot this specification.

Our -mvent1on relates to siphons used in dams Y,or "spillways for the purpo'se of dis-v charging water thro-ugh such d ams or spilll. ways, .and particula'rlylto siphons having throats orI crownsvwholly or in part above 'the high 'or flood water stage controlled byy .said siphons, together with means for charg- 'ing'l or priming and discharging or breaking 'the siphons either automatically or by the manipulation of gates or valves.'

. ln si'phons hereto-fore constructed, the loWeredge of the throat is placed at the lonY s water stage of the pool formed by the dam of siphon atthe y a small difference 1n the two stage-s ot the o-r spillway, so that after the true action, of the Siphon is brokenl no Water will fiow .through-it unless the water is above the low y stage. ,In such siphons the top edge ot the throat is placed approximately at the` high water stage 'oty the pooll in order that the siphons may all be put into action automatically as soo-n as the high water stage ot the pool is reached. llt is desirable for well known reasons to so design the dam or spillway 'as to lmake the difference between the high and low stages ofthe pool as small as possible, and for reasons of economy it is deas short as possible.' lf theheight oit opening throat is made .small to suit pool, the ,width ot that opening measured lengthwise of the dam or spillway must be etanparatively` large in order to 'afford sailifentarea to properly pass the water. vIn :arder to use throat opening of compara-- tively small width it is necessary to make the height of such opening much greater than the amount ofthe di'erence between the Dtwo stages of. the pool when snehjstages l "hcontrolling faetola5-df the design,

sirable to make the' lengthof the structure Sinceit is necessary or desirable toplace the lower edge of thel throat-at or above-the vlower' stage of the poolsiphons `With'high throat will not become primed .automatically when the water reaches .the high stage' as is the case'with' siphons heretofore con-y structed. It is necessary therefore to provlde speclal Vmeans for the 'priming and -breaking'of siphons with throatslplaced'too high'to be primed by the simple 'action 'of the wate'r rising to the high stage, and to provide such means is the object of our invention. f

AThe action of automatic siphons -as here-A 'tofore built vis' clearly shown by Patent i991,907 granted lto George F. Sticlfney, May' 'This specification withI accompanying drawings describes four distinct methods `of water stage'and theupper edge placed ap- 4 proximately at the high water stage above the dam, the priming of the priming sip'hon taking lplace-automatically when the water rises approximately to the elevation of the high Water stage In a third method one or more siphons with high throats are primed by exhausting the -air'Atheretro-m or raretyingy thel air therein by means of the suction created in a suitable air pipe connected to a pipe, conduit or penstock in which water is moving at a comparatively high velocity. In 'a fourth, method one or more siphons with high throats are chargedvby the use'of a priming tank built preferably in the body of the dam, or-spillway or .in one of the abutments therefor.- -Such priming tank is nor-bv mall'y filled with Water which isexhla'usted,

when the time lfor priming a Siphon arrives,

by the controlled -or automatic actionot an auxiliary priming siphon or discharge pipe the size` of which` is small compared with .the principal siphonor siphons of the dam or spillvray.

ln a second method one o r more.

llO

Referring to the drawing in which Alike parts are Similarly designated, Figure 1 is a section of adam or spillway taken through a Siphon which has an inlet well below vthe low water surface and which has a high throat, the lower edge ofV which is to be placed approximately at or above the low water stage above the dam. Fig. 2 is a` secs' tion of a dam or spillw'ay which has fan in.

let placed at the low water stage'and which 'has a high throat, the lower edge ofwhich 4is to be placed approximately at or above i the low water Stage above the dam. Fig. 3 is a section of a dam or spillway taken through a priming siphon placed wholly below the high water stage .and showing a straight conduit connecting the water above the dam to that below the dam and an air pipe. connecting therewith. Fig. 4 is a section of a dam or spillway taken through a priming sifphon having the lower and upper edges o its throat approximately at low and high waterstages respectively. Fig. .4i is a'section through' a curved throat of a'fsiphon showing 'a special `positioning of vair pipes.

- Fig. 5 is a section of a dam or spillway taken the high and low water surfaces, vas is the case of the Siphon shown by Fig. 4. Fig.'

i spectivel a dam s o with high throats and v'the prlmingltanlr through a priming tank whichis to be used, when so' desired, instead ofone of the priming siphons shown by Figs.v 3 and 4. Fig. 6 sho'w's a riming Siphon construotedof metal pipe'em edded in the masonry of the daml or spillway, the upper and lower edges of the throat being disposed at approximately 4controlledby a sluice gate. Fig. 9 iS the.

vfront elevation of a partof adam showing one of a battery of siphons with high throats.

and one v automatic priming siphonhaving its throat with its lower edge and upper edge at ythe lowjw'aterand high water stages rewing `a battery of three siphons Shown by section in Fig. 5'. -Fig. 11 represents a portion of a pipe, conduit or penstock with air pipes connected thereto, suction being produced. in'said air pipes bywater flowing in fthe pipe or penstock at acorn- "trance as Shown. L L shows an alternative paratively high velocity.

R ferring now to. Fig.

: poses of this'invention the outlet end of all Fig. 10 i's the frontv elevation ofV l, the dam or spill-- way is shown as built of masonry, preferably of concrete, 6, being the upstream face; 7, the downstream face; 8, the top and 9, the

siphons with high throats must be placed below the' surface of the water below the dam, or must have such outlets effectually sealedagainst. admission of air as indicated by Fig. 7, while the outlets for the priming siphons, although so shown arel not neces-- sarily to be placed below said water surface'.

V10, is an air pipeentering the Siphon at some convenient point at the vtop o the throat,

whereby air is to be exhausted from the' downstream leg and the throat of the siphonl .by the suction produced by the priming sif phon or otherwise, as hereinafter described.

l1, is an air vent of which there ma be one or more per Siphon, the lower en 12, of vwhich is placed vapproximately at ,the low water'stage above the dam'. and the upper end, 13, of which connects to the throat of the-Siphon at some convenient point. 25, is

lan air pipe provided with an entrance, 24,

placedin the upstream leg 4of the vSiphon below thelow water Surface forthe purposeA of priminganother siphon with high throat bythe use of the Siphon shown. 30, ist valve controlled manually vor otherwise, whereby air may be admitted for the purpose of breaking the siphonic action. M, is the high water and .N the low water stage above the dan-1 as established'v by the use of ftherprop'osed system of siphns. O, is the low water 4surfacef'that would onecessitwbe used .'withjan ordinary dam or spillway bf the overflow type. below'the dam. y

In Fig. 2,- 1 indicates the inlet to the siphon, disposedhorizontally at the elevation ,of the low water surface# 31, indicates a buttress occurring between adjacent srphons; the designations of all 'other numbers lsame as for, Fig. 1. v

-In Fig. -3, 14,1 indicates' a sluice gate, of which a plurality may be used if desired, used for the urpose o shown or through conduit, 29; an`d `15,.1ndi cates the stem by which the` valve or sluice gate" may be controlled from the top of the dam.- 29, shows a Straight conduit connectving the water abovethe d am to. that below the dam, the air ipe, 10, being extended to some point as 18 or the purpose of utilizing Vthe suction produced in the conduit in order to Iprime aj Siphonv with high throat. The

V valves or gates may be placed elsewhere if so desired, but are preferably placedat the enwhen used for Figs. l and 3. In this 'case the are the n gate valve or. I

A pl control- -ling the flow` through t e priming Siphon L, is the Water surface nosaeee .upper edge of the throat, 2, is placed ap,n 'proxiniately at the high water-stage and the lower edge thereofv at the' low waterstage. InFig. 42%, showing' the curved throat oi' a ypriming siphon, 2,4, and 1'0 have the sarneA 'designations as' when used for 1.- l()n shows vthe'special position oitheair pipe to `be used for priming afnother siphon as herevinafterexplained. lo In Fig. 45, 16, is an vair tight tank used as hereinafter explained, for the purpose priming a Siphon with a high throat., 17, is Ia Siphon used for-'removing the -Water fronti the tank, thus producing a rarefaction of the air inthe siphonv to be primed. 26, yis the -outlet of siphon, 17; 28, isa conduit. which inay be used, incertain cases, 'instead of the Siphon, I7 for emptying tank, 16. 27, is they outlet for conduit, 28; 20, is a supply conduit zo'lior tank, 16.; 19, is agate valve or sluice gate for controlling conduit, ZO;y 2l, is a stern for actuating valve, 19, troni the top of the dani; 29., is an'air vent yfor automatically breaking the action of Siphon, 17, when the water falls to low water stage and uncovers the entrance to the vent. L L Shows an Ialternative position of the water surface 'below vvthe dani for cases where it may prove advantageous to place the outlet of the .30 Ipriming Siphon or conduit above such water Surface'.V All other numbers used for Fig. 5

have the same designations as when used -for Fie'. l. A

IIn Figs. 8,9 and l0, 23, designates the 3.5 abutnients of the dani or spillway; all other nuinbers used for these figures have the same designations as already explained for Figs. l' to inclusive. A

ln Fig. 1i, 35, indicates a portion of a '4o pipe', conduit or penstock in which wat-er is iiou'ing at a comparatively highjif'elocity in the direction indicated hy the arrow, 36; 37, isaconiparatively small air pipe tapped into 35; all), is a similar air pipe passing ythrough the side of at 22, and is provided rwith anv extension, fil, turned in the direcytion of the flow of water in The rapidly moving water in 35 produces a' strong suction at 3S or vll and draws air fiforcibly 5 0 through air pipes, 37 and 40, in the direc.t tions indicated by arrows, 39 and 43, Said air being carried away by the water flowing in 35. inasmuch as a substantial suction is produced in a pipe disposed as is pipe, 40,

shown in Fig. il., by water moving. at high velocity through pipe or conduit, 35, in the direction oil arrow, 36, and inasnfiuch as ySub stantial suction* is also produced-near the upper end of a' pipe or conduit through which .60 water flows at comparative high 'velocity 'under a substantial head, such suction being a maximum near Vthcupper end ,of the con-v duit and decreasing throughout itsl length to practically nothing at the lower end, anni .se suoli...suction.Y serving to forcibly' drew air. -1

it for the purpose ot priming the principal siphons of a dani or spiliw.` Any such pine tir-conduit ir; iectrve or its sliapelin plan, elevation or cross section may be uti l which is made practicell liZed' in a Siphon primer. "ilhen 'water flows reely under va substantial ,head from above the dain or troni a. tani: our

duces substantial suction ir e of the shape of the pipe or conduit leading from such reservoir and it is Athe pur or ou'r invention to utilize such suction for the priming oit the principal siphons 'of a dein or spillway and Such device we terni a Siphon pri-nier.

in Fig. G, a priming siphon made ci? metal pipe is shown. The designations-of nurnbers l, 2, 3, 4, .5, i() and 1l. are the saine as for Fig. il. v50, is a recess in the top'o the vdani which may be'proriiled it desired; o2,

' as Shown, bringing the upper upon thereiis no flow -throuvh the 4water stage,

`as the issuiicient are couplings in the pipe. whereby the L .Q a t throat, L, may be readily renioiv` i ene. clenncd in case it should become cloL replaced it broken. y

Fig. '.7 shows in sectione portion oi' a dani V or spillvva'v in the vicinity oi 'the outietot a Siphon withl high throat. '71, is the den stream face of the dani; 9, is the'base; L, the surface of the water below the dani; 3, is the outlet. in order to -prevent the entrance of air through the outlet the downstream leg of the siphon, near the outlet, has an upturn,

e( ifo, 3st,? L) licicntlyI heloi.V the lower e te esti a basin in the Siphon in which will al ways stand to the elevation oli Bij-, thus filling the entire cross section oit the conduit below ,Se with water.

I'lhe action of the system., shown by Fig.

8 in elevation andbv Figs, l 'and 3 1n section, isas tollowsrdWhen the power plants at the darn are using the entire flow' of `the stream the sluice gate, le, is closed, wherepriming Siphon or conduit. if then, there a. liow through the other siphons the' pool will he gradually lowered -until the low stage, N,

is reached, uncovering the air vente, l2, whereupon the siphonic action will 1he broken and the siphons cease action. So long as the powerl plant continu to 'utilize the eractfaniount of 'water delire. ed to the pool the Water lever will vremain stationary. Upon an increase of ilew', howev the level will rise until, as it approaches the high M, the xsluicc gate, lll-,is to be opened. yinasmuch as the throat ci the priming eiphon is entirely below the level of the water surface, theaction o'fvthis Siphon or of theeonduit will be established a soon opened. it this Stage of the water surface all vents, 12, are

priming Siphon or conduit acting through the p1pe.s,'10,' inac'cordance with the well known` action of water-"passing through jcl osed -'onduits at high velocities. The suctlofn will continue as long as -the priming 'runs' full and-until the imprisoned lfisee'ntirely exhausted from the battery of 4'jsiphons, assistance being had toward the close of 'the exhaustion by t e well known action .of the water flowing over the lower edge of 'the throats, 2, of the siphons, an actionwhich A with high throats will be broken and water begins? as soon as the imprisoned air has' vbeen suicientl rareied to raise the water in the 'upstream eg of the Siphon higher than 5 the'lower edge of the throat.l ""If a suiiicient number of siphons has been rovided they will discharge somewhat more than., the maximum flow of the stream and thurefore the water level will begin to fall Las as the siphons are all running full;

the surface will continue to fall until vents, 12, are uncovered at the lowwater stage, N, whereupon the siphonic action of the siphons will discharged 'by the priming siphon onl If now the flow ofthe stream in excess-` of at ,used by the power plants is in excess of that discharged by the priming siphon, the water surface will begin to rise, air vents, 12,

lwill be covered, the battery, of siphons will be primed again as before and the water surface will fall again until the air vents are uncovered, the cycle being indefinitely and automatically repeated until the sluice gate isk closed or untilthe excess flow of the streamfis less than the -discharge of the V.priming siphon.A When this conditionarises the' water surface will begin to fall below ,the'low water stage, N, and the flow of the 45' i 'the use'fof the sluice gate and the water surface held at the low stage until the excess lowragain exceeds the capacity of the priming siphon, whereupon the sluice gate will be fully opened and the automatic action of the battery of siphonsrestablished thereby. The action of the system, shown by Fig. f8 in'elevation and by Figsi. 1 `and l 1n section, is as follows'zrWhen the power plants use the entire flow of the stream the water will standfat the low stage', N, or at the elevation of the lowerledge of' the throat of the priming siphon. lUpon an increase. in flow the level', will rise until the throat .of the priming siphon is filled and thatl Siphon is put inaction. .The water surface w1ll then besuiliciently high to seal a1r'vents,"12, and imprison the air `in the throats, 2, and

downstream legs, 5, of thebatteryof siphons.'

'of the consumption of the power cient size to secure this result priming siphon is Ato be thereafter controlled l be rarefied by the suction of the' priming Siphon acting through air pipes, 10, exactly as already explained for the manually controlled priming Siphon shown 4by Figs. 8 and 3. Thus at the tlme the high water stage,

M, is reached all siphons will be brought .automatically into action and the water level will begin to fall and continue'to fall untill the airventsare uncovered, breaking the action of all s1phons at the low water stage,

N. Ifat this moment the flowy is in excess lauts, the water will again be into rise and) the cycle above described will` e indefinitely and automatically repeated.

The action of the system, shown in eleva-v t1o n by Fig. 8 and in section by Figs. 1 and 5, 1s as follows z--When the power plants are "using the full flow of the stream, the water will stand at about the low state, N; valve, 19, 1s to be openpermitting'water to enter theair tight tank, 16, through-inlet, 20,

which is to have a cross section sufficiently great as compared with either siphon, 17,

or outlet, 28, to keep the tank'always' full when valve, 19, is open. v-Taking 'first the case wherel siphon, 17, is used to' the exclusion of outlet, 28: U on an increase inthe flow ,of the stream, the seals the air vent, 22, and upon reaching approximately the high stage, M, automatically starts siphon, 17, which draws water from the tank at a less rapid rate than it isV supplied by inlet, 20. Valve, 19, is now to be closed, upon which siphon, 17 will begin to empty the tank which tends to produce a vacuum at the top thereof. Air is then drawn into the tank through air ipe, 10, from the throat and downstream eg of a Siphon with a high throat until the air therein is -suiciently rarefied 4to start the full flow of the siphon, the tank bein of suliefore all water is withdrawn-from it by siphon, 17. The tank may be made, if desired, large enough to prime all of the siphons withhigh throats, but as this makes necessary the4 conf #struction of a needlessly large tank, it is l flow of the first Siphon is established there is setup a suction';,on the art of this siphon, in air pipe, 10, which will reverse or partly reverse the How in siphon, 17, thus filling,in wholeor in part, tank, 16, or tending to fill said tank depending on the dproportions-of 17 v and pipe, l10, an the extent or siphon,

,T he flow in the first amount of thesuction.

water level rises,

siphon having been established, it, in its turn, has the well known eiiect of producing a suction at the entrance, 24, of air-pipe, 2 5, lwhich, as shown, connects any convenfient''pointbelow the water surfaceoflthe upis used in lace of siphon, 17, 'the tank wil a@ beemptie Kif'valve, 19, beiclosed whenever streariii leg oit-the 'first 'Siphon' with'v the- Q -(iliig. may` be connected, ,as is evid`ent,.

'conveniently to 'the lowe'r edgeotthroat, 2,`

as indicated by -pipe 10a in F'g, 4, it haring' been found that the most, powerful suction is.prodiiced through the additionaleffect of. centrifugal force at the` lower or convex sui- 'tace of the material vforming: ,the Vcurved v throat of .theysiphon Then the sipho-ns have all lteen -piiined and are running full,

the Water' surface will begin tov fall andthe m air-vents, 12will b e exposed ywhen the sur-- .tace reaohesthe lowlstage, N, whereupon 'the siphonic' action will be broken landthe surface vbegin tol rise again. For the pur-I pose of holdingwithin tank, 16, all thewa-r tergit'then contains, air vent, 22, breaks the' action. siphon', 17, at Vthe instant 4of or justjfbefre the action 'of the battery of.

siphons is. broken. ll/Vith the arrangement shown the repriming of 4the siphons 'cannot 3.a, .beautolinatically accomplished.- 'It is n ec'essary to open valve, 19, leaving'it open until -the water has risen suciently. to charge siphon,y 17,' and then closing it, lwhereupon water will he drawn from, tl'ie'tank, the' air in the throats `will be rareied, the' siphons will beagain put into service exactly as heretofore .described and ,the cycle will be 'repeated 'incase outlet, 28, (Figs. '5 and 10)l the water 'falls to the low stage admitting air e 'through vents, y 22, to the throats .of the phons and thence through'pipes, 10, to the vv"tank, 15. Conduit, 20, being :made sufficiently larger than outlet, 28, when valve,

` '19, is opened tankN 16', will soon become filled. i 'When .fthe waterv has risen high enough 'to seal'the vents of the Siphon 'and valve', 19, is closed the tank' will 1oegin to 'empty 'through outlet; 28', and.' the irst si hon will be primed by the suction'prodiced in ,the tankexactly' as already de? kscribed for the use of Siphon, 1.7.

The action of the priming siphon shown at in' ysection by/j Fig. 6- is exactly the Same as' .''or the priming Siphon shown by Fig lathe yjfdii/ierenee ybeing vin thedetails ,of construction, v

In case any p nativ/ely small capacity it may be 'desir-- zahley tofplace, the lower'edge of the throat sgmewh't below the -.low water stag'e, in Which'case asmall but immaterial amount f water may be constantly wasted1 throiitgh'I such Siphon without' affecting the spirit or` intent of oi'ir invention.' In like manner .theaipper edge of the throat ofa' 'priming be used, their throats may be disposed at varying elevations, bringing the siphons' rations. of the water surface above the dam 'and thus tendingto produce a more nearly 'constant elevation of that surface. In case reasonably -ie constantly wasted,.it maybe desirable to put' the priming siphon'swith 'their throats Iwholly below the' low'water stage above` the dai'n' .without affecting .the spirit' or intent of our invention, in whih case 'such priming siphons will .constantly 'will be primed as soonl as the water surface 'rises sufficiently to seal its vents. The ,air

Siphon' 'above -the top of the masonry as vany Vconvenient point.' -ln cold climates .'thesepipes are subject to being 'trozenwhen 'filled with'w'atema state' which will occur when the siphons are' in service.4 :Since this tive, anyknown method may-be adopted'for heating 'or protecting suchpipesto prevent freezing a Although Figs. '8g and- 9 Show only one high throats, i-t isth'e intent of our inven- -tion-that a separate priming Siphon may-.be used, it desired, for each Siphon with a high throator for groups of tworfmore such siphons; 4such 'individual lpriming siphons wouldpreferably but not'ne'cessarily be con,- structed of metal pipe as indicated by Fig. 6. ltr is tobe'uiiderstood thatl air| pipes, 25, shownin Fig. inay'heused inpla'ce'pf pipes, '10', shown in'Figs. 8 and-9, ol vice versa, and that other arrangements o 4pipes maybe made, although not shown, which will serve tocarry out the spirit and intent of our invention. i

With 'the arrangement' of air'j-pipes, 25, .shown by Figs. 10 and 1', the air-inlets, 12, may be placed each at a different eleva-tion between the stages of water above the dem. It in Fig'. 10

above'low water stageythat for the right hand Siphon afli'ttle below high water stage riming s iphon be of comyand that for the center jsiphon' intermediate between the other two,' `the' action will be asf follows: `With all siphons operativeandl the water `at high stage'thewatersurface will begin to fall 'until Vit uncovers-vents',12, of the right hand siphon.- `It nowthe other pipes, 10, -m'ay-be conducted from sip'hony to freezing would render the system 'inopera.

' siphon may be placed lower than the high. water stage iii case itis desiredto start the siphonic action of any .Siphon orI siphons-bef fore the high water stage is reached; if de. sire'd, in. case a plurality ,of priming siphons' with higl.` throats into action at varying ele- 'run full and, any siphon with high throat' priming Siphon for albatteryofI siphons with also, therese surplus of lwaterwhich may shown or may be buried inlthe` masonry at.

ios

limits 'edby the 'low and h'igh two siphons are of insiiiicient 'capacitytoigo n service at comparatively infrequent inter.

ca rry the excess flowjof the stream thewater will begin tolrise again until the' vent is sealed,` whereupon thefright hand Siphon will be-again put into "service and theautomatic cycle .will be-'repeated until the excess flow is less than the, capacity oftwo siphons.

When this condition obtains the Water 'sur-V` face 'will continuato fall until vents, 1 2, ot"l the center Siphon are uncoveredand't'his Siphon-will thenbe alternately automatically broken and lprimed'eicactly as already described for the right hand Siphon. Similarly the left'hand Siphon will operate through an automatic cycle whenever the excess flow is a lmaterial quantity but less than the capac'ity of 'a single Siphon, This system of varied elevation .ofgvent's is to be preferred as it brings the use of the Siphon primer into vals, in fact Such primer.- will be utilized only upon .an increase in-'flow after a period during which the power plants are utilizing theentire flow of the stream. The use of 1 action 'is automatically broken by the use of proximity to the dam or Spillway.

suitably disposed-air vents, cornes within the scope of'our invention.

Although Figs. 1 to 7, inclusive, show the siphons'or tank `built in the darn or spillway as distinguished from Athe abutment,'1t is the intent of ourinvention that a tank or tanks,

'ora Siphon or siphons may be built to `operateffas heretoforedescribed-in either orin both -abut'ments, or elsewhere' 1n convenient by Figa,

In the case ofthe Siphon shown i. inlet land air vents, 12, are merged into one opening. The 'action of this si hon is sub. stantially the same as with the Siphon shown.`

'by Fig.V 1, the siphonic action being broken whenever'. thef'water falls to approximately .the' lovvv water stage thereby admitting `air into the throat ofthe si'phonbelow the-upper l edge of inlet l1. g

In lthe accompanying drawings the siphons are'shownfwith a Wider throat, Ias measured longitudinally of the dann-than thel WidthV of'inlet oroutlet, but `such Siphons niay be built whenever desirable with the 4width of 'throat equal to or even less than the width of' inlet o-r outlet' without in theleastatfecting the intent or spirit of o`urin`ven tion.

Although not essential to our invention,

4air valves, 30, may be-.inserte dl inV air` pipes, v

10, or 25,- where Shown 4in the drawings 0r elsewhere, for the purpose of` affording-wntrol of the action of some or'all of the .siphons, the' action-v of 'thejsiphons being broken whenever. air admitted to 'the in of such valves.

vmore siphons having throats whol part above theelevation ofr'thehig water throat" in suflicie'nt quantity and. restored when'l the Supply of air iS'cut off by the clos- .I hatl we claim as our invention and de sire to secure by Letters Patent is:

more siphons having 4.throats place wholly or 1n part abovethe elevation of :the high water Stage Vabove the dam, such Siphon or siphons being4 primed by a Siphon primer.

Y. 2. A ,dam or spillway containinkrone or` more siphons havingV throats placed wholl or in partabove the elevation of the hig water stage above the dam, suchsiphon or siphons being primed by a priming Siphon,

cally broken by the'admissio'n of air to the throat through a vent-'or vents connecting the throat to the upstream face of thedam at the elevation of the low water stage above the dam, substantially as described. 3. A damv or spillway containin more siphons with the throat of'eac Siphon one or ,70 1. A dam or splllway contairim one or ,the action of such Siphons beingautornatiplaced wholly orin part above theelevation i of the high yvater stage above the darn; the inlet of'each Siphon beingplaced well below thelowwater stage above the darn; each Siphon being primed or actuated by a prim- 111g slphon orsiphons.

4. -A dam' o-r spillway containing one or 4more siphons with the throat ofeach Siphony "placed wholly or in part above .the elevation of lthe high water stage above the dam; the

inlet-of each 'Siphon -being' placed well below `the low water Stage above'the dam;l and a Siplflfm pri-mer. l 1 n '5. A dam or spillway containing one or more siphons with the throat of. each Siphon placed wholly for inpart above the elevation of the highv water stage above'the darn; the inlet of each Siphon being placed well below the low. water Stage'above the dam; anda vSiphon primerythe action of each Such Siphon -being automatically -broken'by the admission of airto the throat through. a ventV .or 'vente Vconnecting -th'e throat -to the 11plstream face of the dam atthe elevation' lof the low water stage' above the dam, substantial'lyas described. v

6; A dam orspi more- Siphons, each of' inverted U-shaped4 form; with the throat of each Siphon placed 'wholly' or in partabove the elevation of the high water stage above 'the dam; with fone leg of' each Siphon `extending through the upstreamface ofthe dam yor spillway at av-'point wellv below the' low water stage above the dam; the other legfof the Siphon extending throughv the' downstream. face .of

the dam or spillway. at an elevation lower thanv the. openingr forv the upstream leg; 'and asiphon primer. I7. A dani'or Spillwfay containing one or or in llway `containing one `or izo Stage above the dam; suchsiphon or siphons A 'bei'ng'p'rimed bythe autoinatic action of one or more priming siphons eachwith the lower vedge,andxnpperjedgeiof Iits throat placed l''approx'imately at the lowland high water stages respectively above the dann.

`. S', A. dani 'or spillway containing oie 'orv f 'Y m regsiphonawith the throatof each Siphon placed lwhollyor in partabove the elevation of the highfwater stageabovethe dam; with tlie inlet eifeach Siphon placed well below tl'ieflow water Stage. above the dam; each' l Siphon being primed by' the automatic action ot one'lor morey priming 'Siphons each with "the lower edge'and upper-'edge ot its throat placed approximately at the... low and high.

water stagesrespectively above thedam.l y Q .'A' dam pr Spillway.-containing one'or more `siphpn`s;. each'ozt inverted IU-shaped ot' the high .water s ta lor inpart above the-ele'vation of the high.

form; with theth'roat ot'each Siphon placed `wholly ory in 'part abof'eth'e elevation of the high'watei" stage aboveuthe dam' with one t: Q J

legof each Siphon. extending through ythe' upstream' face 4olf 'theV dani or spillwayV at. a

point well bellow yt-he low water'stage above the the downstream. face at an eleva-tionlower than that of'the 'opening for the upstream leg'; leach Siphon being primed by the auto. matic action of oney or more priming' Siphons each with the lower edge andl upper edge of its throat placed approximately at the low and high water stages respectively above the 'dam.

, lO'uln a dam or sp'illway, a plurality of Siphons. each provided with-an airvent or vents piercing the upstream face of the dam between the high and vents being placed at varying elevations and Serving to automatically break the Siphonic action of the various Siphons at varying stages oit the water surface above the dam.

` 11. A damory spillway'containingone or more siphons having throats placed Wholly or water "stage above the dam, Such Siphon or s iphons'being primed by meansl of the suction vproduced in .pipes connected to -the curved lower surface of the throat of the priming 1Siphon, substantially .as described.

12. A. dam or spillvvay containing one or more siphons with the throat of each Siphon placed wholly or in part above-the elevation 'e above the dam;the

inlet of each Siphon being placed Well below the low water stage 'abovethe damp each Siphon being primed by means of the-suction produced in pipes connected to the curvedlower Surface ofthe throat-of the` priming Siphon; substantially .as described. 13. Av dam or spillwa'y containing one or moresiphons having throats placed Wholly Water Stage abovethe dam, Such Siphon` or Siphons being primed by means of the suodain,. the. o't-her'-leg extending through4 low water stages, Suchin part above the elevation of the high,

' the lion produced .in pipes connected to the curved. lower Surface Iof the throat 'of al priming Siphon; `thb action1 of each ysuch siphon being automatically.'broken by the admission ot' air to the throat through 1 vent,- orvents connecting the throat tothe upstream fac'e of the dam at the elevation of the low water stage above the tially as deseribed.

let'. .Si dam or spillwaycontaining one or more lSiphons, with `the throat of each siphon placed wholly or'in part above theelevation oi the high water Stage above thedani; the inlet of each Siphon ,beingy placed` well be.-

' lov.v the low water Stage above the dam ;e ach dam, Substanwholly or in partabove-the elevation of the high water Stage above the dam; with one leg ot'each Siphon extending 'through-the upstream face of the clam or Spillway at a l` 'point' well below the low water stage above the dam; the otherleg. of the Siphon extending throughl the downstream face of the dam or spillway at an elevation lower than the.V opening for the upstream leg, each Siphon being primed by means of the suction produced 1n pipesiconnected tothe curved lower Surface of the throat of the 'priming Siphon;

the action of each Such Siphonbeing auto` matically broken by the admission of air -to the throat through a` vent or vents connectf4 ingv the throat to the upstream face of the dam' at the-elevation of the low water stage above the dam; substantiallyasfdescribedt '16. A damor spillway containing one or `more siphons having throats placed wholly or, in part above the elevation lof 'the high Water stage abovel the dam, suchsiphon or siphons having the upperl edge of the inlet yplaced 'approximately at the elevation oA the low waterstage abovefthe'dam; suchlsiphon or "siphons being 4primed by the action `of a priming conduit; and means for exhaust-ing air therefrom. l j 17. A dam or spillivay containing one or more siphons having throats wholly or' in part above the elevation of the high water stage above the dam; each Siphon being of inverted U-sha'ped form with one leg extiendin-g through the upstream -face of the dam or spillway at a point well below the low'water stage above the dam,.the other-leg extending 'through the downstream face 'at an elevation 12m'- lower than the opening for the'upstream leg I each siphon being primed bythe automatic action ofone or more priming siphonsg, the action of each Siphon being automatically broken by the admission of air'to the throat through a. vent' or vents' connecting "/the throat. tothe upstream'face ofthe-dam, subf ,stantially as described.

` 18. A dam or .spillway containing one or more siphons having .throats placed wholly or in Part above the elevation of the highv `Water stage above the dam; such Siphon or Siphons bein primed by they action of a priming con uit and means 'for exhausting the air therefrom. y 1

19. A dani vor spillway 'containing one or more'siphons having throats placed wholly or infpart above the elevation of the high Water stage above the dalnwith the inlet of each Siphon placed well below the low water stage above the dam; such Siphon or siphons being primed by the action o a priming conduit; and means for' exhausting the air tlfierefrom.l

Aing for the upstream'l 20. A ldarn or spillway containing one or more siphons having throats placed whollly; 'or in part above the elevation of'thehg Water stage above the dem; each Siphon being of inverted U-shaped form with one legl of each Siphon extending through the up.- stream face of the dam at a point well below the low Water stage above the dam, the other leg extending through the downstream'face at an elevation lower than that of the open'- i eachsiphon being primed by theaction o a priming conduit; and means for exhausting the air therefrom.

' 2l. Adam or spillway containing one 'or more siphons, .each Siphon being prlmed by the action of a priming conduit; and means for exhausting the ai'r therefrom. 

